2677
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2678
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2676
- Möbius Function
- -1
- Radical
- 2677
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 71
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 388
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Numbers k such that (1,k) is "good".at n=36A000696
- Primes p of the form 3k+1 such that sum_{x=1..p} cos(2*Pi*x^3/p) < -sqrt(p).at n=37A000923
- Numbers k such that phi(2k+1) < phi(2k).at n=35A001837
- From relations between Siegel theta series.at n=31A006476
- Balanced primes (of order one): primes which are the average of the previous prime and the following prime.at n=26A006562
- Where the prime race among 7k+1, ..., 7k+6 changes leader.at n=23A007354
- Coordination sequence T1 for Zeolite Code EUO.at n=32A008095
- Coordination sequence T3 for Zeolite Code EUO.at n=32A008098
- a(n) = floor(n*(n-1)*(n-2)/16).at n=36A011898
- First time that the Grundy function G(x) for "subtract-a-Fibonacci-number" takes the value n.at n=10A019307
- Numbers k such that the continued fraction for sqrt(k) has period 19.at n=21A020358
- n-th prime p(k) such that p(k) + p(k+9) = p(k+3) + p(k+6).at n=32A022893
- Primes that remain prime through 2 iterations of function f(x) = 9x + 4.at n=36A023266
- Expansion of e.g.f. sin(x)*sin(sinh(x))/2 (even powers only).at n=5A024230
- a(n) = (d(n)-r(n))/2, where d = A026066 and r is the periodic sequence with fundamental period (1,0,0,0).at n=20A026067
- Primes p such that digits of p appear in p^2 and p^3.at n=19A030085
- a(n) = prime(10*n - 2).at n=38A031384
- Primes of form x^2 + 23*y^2.at n=58A033217
- Primes of form x^2+51*y^2.at n=27A033233
- Primes of form x^2+69*y^2.at n=19A033244